Automatic switching device for telephone systems.



L. DE FOREST. I

AUTOMATIC SWITCHING DEVICE FOR TELEPHONE SYSTEMS.

APPLICATION mm mu 7. 1915.

1,170,882. S Patented Feb. 8,1916.

- nections and establish connection with the To all whom it mayconcem incense.

LEE m: ronnsr, ornnw York, N. Y.-

auromarrcswrrcnmo DEVICE son rnnnrnonnsvsrnmsn Specification or Letters Patent.

Patented Feb. s, 1916.

Application filed 111177, 1915'. Serial No. 88,399.

Be it known that I, LEE on Formal, a citizen of the United States, residing in the city' of New York, county of Bronx, and State of New York, have made a. certain new and useful Invention in Automatic Switching Devices for Telephone Systems, of which relay device for automatically; controlling more fully hereinafter.

the following is a specification.

This invention relates. to automatic switching devices for telephone systems, and

is especially designed for use in connection with radio telephone systems. a

The object of the invention is to provide a the transmitter and receiving 'c1rcuits.

A further objectof the invention is to provide means which are automatic in action to connect the transmitting apparatus with the radiating antenna system when the voice is to be transmitted and to disconnect said conreceiver when sounds are to. be received.

.Other objects of the lnvention will appear The invention consists substantiall'yin the construction,combination, location and relativearrangement of parts all aswillbe'more fully hereinafter set forth, as shown in the accompanying drawing and finallylpointed out in the appended claims.

Referring to the accompanying drawing,-

j Figurel is a view indiagram illustrating one form of arrangement of automatic switching device embodying my invention.

my invention.

Fig. 2 is a similar viewshowing a modified arrangement included within the scope of One of the defects oi wireless telephone systems as practically; operated is that it is impossible to carry one continuous back and forth communication without switching the connections from transmitting-to receiving conditiomand. back again so as to utilize the same antenna system both for receiving and transmitting, it being impossible to receive and transmit at the same time with the same antenna system. In practiceit is customarily proposed to employ a manually.

operating switch. to effect the proper shift -T ingof the circuit connections. This mate rially impairs the efiiciency'and the speed of telephonic communication since an operator must throw the switch after talking into the transmitter so as to place the apparatus in condition for receiving before he canreceive.

a message transmitted to hissta'tion' and v.receiving condition at the V0108 sounds.

forehei can again transmit a message.

"It is among the special purposes-of my present invention to provide an automatic switch device which is voice controlled to the extent of efiectingan automatic connection of the circuits into a transmitting condition by the sound waves of the voice when a message to be transmitted is spoken into the transmitter, the apparatus "being normally in receiving'condition and being restored to cessation of the In the accompanying drawing I have shownvarious v arrangementsfor' accomplishing these purposes. In Fig. 1 of the .dra'win N is the antenna of a radio system which 1n the transmitting part thereof includes the usual oscillator K, the terminalsof which are connected to a suitable current source through the leads S. Associated with the oscillator K in the usual manner is a capacity P and inductance V. J, K are terminals designed to be put into circuit.

connection with the antenna N, through a conductor arm 2. Theiterminal J is in circuit with the receiving or detector circuit through wire X in the usual manner. The terminal K is in circuit through transformer. coil T, wire 5, to the back contact L of amicrophone. The frontcontact L of which carries thediaphragml) in the usual manner, the carbon or other conducting granules or medium C being interposed between said-contacts L, L". .The microphone dia hragm Dis connected to earth at E. M is e mouthpiece of the microphone. When the contact lever 2 is in contact with terminal K, the antenna earth circuit may be traced from the antenna N through the tuning inductance W lever. 2, terminal K, coil T, 'wire- 5, through the microphone to the earth" at E. This is the arrangment for transmitting. When the conductor'lever 2 is in contact with terminal J the antenna is connected" to %he receiving system. It will be observed t at the transformer coil T is associated in the usual manner with the in-' 'ductance V of the oscillating system.

In practice the conductor lever 2 is normal-ly-in contact withterminal J and in ac- 7 back again into transmitting condition beeordancewith ;myinvention I propose to.

provide automatic means operated by either the so nd waves of the voice or' by exhalation 0 the breath in speaking toldisconnect the lever 2 from terminal J and .to'connect it 30 breath ex with terminal K. When the apparatus is in normal condition, that is when the antenna is connected to the receiving system and the antenna earth circuit is opened at terminal K, it is also preferable to open the oscillatin circuit. I therefore provide a terminal. in, the oscillating circuit with which cooperates a conductor member ,3 which is associated with the leven2 to move coincidentally therewith so that when lever 2 is in conta'ctwith terminal-J, member 3 is out of contact with terminal L and when -lever'2 is in contact with terminal K member 3 is'in contact with terminal L In the 5 latter condition the oscillating circuit is closed and the antenna system is completed to earth as above explained which is the con-' dition for transmission. Associated with the lever 2 and member 3 is a member Z constituting the armature of a slow relay S, a coil of which includes a battery B, a suitable and preferably adjustable contact Gr extending into the mouthpiece M of the microphone and with which-cooperates a contact F on a loosely mounted member F suspended'within the mouthpiece M and transversely thereacross in position to be held toward the contact G by the action of sound waves impingin thereon or by the action of the aled bythe operator when speaking into the mouthpiece.

The operationis as follows :--Assuming that the apparatus is in the condition shown in Fig. 1, z. e., in condition for receiving communications, the one receiving the communication, in-order to reply, without manually operating-any switch, merely talks intothe mouthpiece M of the microphone, the ex- =halation of the breath, or the force of the 40 sound waves impinging on the diaphragm 'F, causing the contact member F thereof to make contact with the ,contact member G, thereby closing the circuit of 'and energizing the relay 'S thereby attractingithe I armature Z, breaking contact with arm "2 and the lead X to thereceivin apparatus, and completing the circuit 0 the antenna through the microphone, through arm 2, contact K, diahragm D and earth E, and at the same, time I y meansof arm 3 and contact L providing the :necessary Qoscillating current through leads S, inductively-associated with the antenna earth 'systemthrough the coils V, T. It will be seen that whenspeech ceases, con

tacts F and G separate thus opening the circuit of relay S and allowing the switch shown in Fig. 1, and putting the system in condition to receive communications as 60 'above described.-

In Fi 2 1 have shown asimilar' arrangement wierein I employ a different means 'for' automatically switching the antenna to the receiving and transmitting systems. In

"cc-this form of my invention, I replace the 'tact with the conducting fluid at all times,

diaphragm and contact arrangement of F,

fluid It is located in the tube which also has a terminal at its lowest point to insure consaid terminal Y being the remaining terminal of thecircuit of the relay S. -The re- I maining elements of the device are the same as described hereinbef'ore. The operation is also identical except that the energizing of the relay S, is secured-by the exhalations of .the breath, or the sound waves or both, to-

gether'with the capillary action of the tube 0 and conducting fluid R, completing the electrical connection between terminals Y and Q.

It will beunderstood that manyother arrangements will occur to those skilled in the art for accomplishing the objects and purposes of my invention without departing from the broad. scope thereof as defined in the claims.

It will be readily seen that I have supplied an automatically operated switching device that is exceedingly simple in construction and which will allow a wireless telephone station to be operated as both a receiving and a transmitting station, without manually opei'atingswitclies, and which causes no delay in the change from receiving to transmitting arrangement. or vice versa, and

eliminating the possibility of having messages cross each othervby having two stations transmitting at the same time, as' such a condition would be readily detected.

Having now set forth the object and nature of my invention, and having described arrangements for carrying out the same, I claim: a 1.- In a radio telephone system, an antenna, receiving and transmitting circuits, said antenna being normally connected to said receiving circuit and means controlled by the voice for automatically connecting said transmitting circuit to said antenna when said system isused for transmission. 1 15 2. 'In a radio, telephone system, an an- =te'nna, receiving and transmitting circuits,

and means controlled by the voice for automatically connecting said transmitting circuit -to said antenna only when said antenna 120 .-is used for transmission. ,arms 2 and 3 to again resume the position -3 In a radio telephone system, an antenna, receivin'gand transmitting circuits, vvoice controlled means for automatically connectingsaid transmitting circuit to said 12 antenna and means for maintaining said connection-only as long as transmissions are made.

4 4. In a radio telephone system an anvoice controlled means for automatically connecting said 'transmitting circuit to said antenna and means for automatically breaking saidconnection when transmission ends.

5.-In a radio telephone system, an antenna, receiving and transmitting circuits, and voice controlled means to connect said antenna to said transmitting circuit.

5. In a radio telephone system, an antenna, receiving and transmitting circuits,

and means operated by the exhalation of the human breath .in speaking for connecting said antenna to said receiving circuits.

, 7. In a radio telephone system, an antenna normally connected to a receiving circuit, a normally'open transmitting circuit, and voice controlled means to automatically open said receiving circuit and close said transmitting circuit.

8 In a radio telephone system, an antenna normally connected to a receiving circuit, a normally open transmitting circuit, and means controlled by sound waves to antomatically open said receiving circuit.

9. In a radio telephone system, an antenna normally connected to a receiving circuit, a normally open transmitting circuit, and means controlled by sound waves to automatically close said transmitting circuit.

10. In a radio telephone system, an antenna normally connected to a receiving circuit, a normally open transmitting circuit, and means controlled by the exhalation of the human breath in speaking for opening said receiving circuit.

11. In a radiotelephone system, an antenna normally connected to a receiving circuit, a normally open transmitting circuit, and means-controlled by the exhalation of the human breath in speaking for closing said transmitting circuit. I

12. Ina radio telephone system, an antenna normally connected to a receiving cirtems, and voice controlled means for automatically operating said switch.

15. Ina radiotelephone system, a receiving system, a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said systems, and voice controlled means for operating said switch, said means being operated by the closing of a normally open circuit.

16. In a radio telephone system, a receiving system, a transmitting system and a common antenna therefor, a switch for connecting said antenna to either of said systems, and means for operatingsaid switch, said means being controlled by a make and break circuit device and voice controlled means for operating sa-id'device.

17 In a radio telephone system, a receiving system, a transmitting system and a common antenna therefor, a switch for connecting .said antenna to either of said systems, and means for operating said switch, said means being controlled by a make and break circuit device, operated by sound waves.

1-8. In a radio telephone system, a receiving system, a transmitting system and a common antenna therefor, a switch for connecting said. antenna to either of said systems, and means for operating said switch, said means being controlled by a make and break circuit device operated by the exhalation of the human breath in'speaking.

Intestimony whereof'I have hereunto set my hand'on this 21st day of June, A. D.

- DE FOREST. 

